Method of making carbonoyl sulfoxide derivatives

ABSTRACT

Intermediate compounds and the process of manufacturing herbicidal active sulfoxide and sulfone compounds are described herein. The intermediate compounds have the following generic formula:   wherein R is selected from the group consisting of lower alkyl, haloalkyl, alkoxyalkenyl and alkenyl; R1 and R2 can be the same or different and can be selected from the group consisting of lower alkyl, cycloalkyl, alkylcycloalkyl, alkenyl and alkynyl. The active compounds are made by reacting the intermediate compounds with an oxidizing agent.

Tilles et a].

[ METHOD OF MAKING CARBONOYL SULFOXIDE DERIVATIVES [75] Inventors: HarryTilles, El Cerrito; John E.

Casida, Berkeley, both of Calif.

[73] Assignee: Stauffer Chemical Company,

Westport, Conn.

[22] Filed: June 18, 1973 [21] Appl. No.: 371,326

Related [1.8. Application Data [63] Continuation-impart of Ser. No.280,371, Aug. 14,

1972, abandoned.

[52] US. Cl 260/551 R; 260/455 A; 260/607 A; 71/100; 71/98 [51] Int.Cl.. ..C07C 103/32; CO7C 103/56; CO7C 147/ 14 [58] Field of Search260/551, 561

[56] References Cited UNITED STATES PATENTS 3,326,663 6/1967 Soloway eta1 71/103 July 22, 1975 Primary Examinerl-Iarry l. Moatz Attorney,Agent, or Firm-Daniel C. Block [57] ABSTRACT Intermediate compounds andthe process of manufacturing herbicidal active sulfoxide and sulfonecompounds are described herein. The intermediate compounds have thefollowing generic formula:

wherein R is selected from the group consisting of lower alkyl,haloalkyl, alkoxyalkenyl and alkenyl; R and R can be the same ordifferent and can be selected from the group consisting of lower alkyl,cycloalkyl, alkylcycloalkyl, alkenyl and alkynyl. The active compoundsare made by reacting the intermediate compounds with an oxidizing agent.

2 Claims, N0 Drawings METHOD OF MAKING CARBONOYL SULFOXIDE DERIVATIVESCROSS-REFERENCE TO RELATED APPLICATION This application is acontinuation-in-part of application Ser. No. 280,371 filed Aug. 14,1972, now abandoned.

DESCRIPTION OF THE INVENTION This invention is directed to a novel groupof compounds which may be generally described as sulfoxide and sulfonederivatives of thiocarbamates which are highly active herbicides. Thecompounds of the present invention are represented by the genericformula:

wherein n can be 1 or 2; R can be selected from the group consisting oflower alkyl, haloalkyl, alkoxyalkenyl and alkenyl; R and R can be thesame or different and can be selected from the group consisting of loweralkyl, cycloalkyl having 3-8 carbon atoms, alkylcycloalkyl, alkenyl andalkynyl.

The above-noted compounds can be prepared by reacting an oxidizing agentsuch as peracetic acid or mchloroperoxybenzoic acid with a thiocarbamatecompound corresponding to the following formula:

wherein R, R and R have been defined above. The reaction is carried outin the presence of an inert solvent such as chloroform, methylenechloride, benzene, and toluene, and at a temperature of from about--25C. to about 60C. The amount of oxidizing agent used must be at leastone molar equivalent to form the sulfoxide derivative and at least twomolar equivalents to form the sulfone derivatives. The reaction iscompleted when no oxidizing agent is left within the reaction mass.

The thiocarbamate compounds are known herbicides and their method ofsynthesis is known; see U.S. Pat. Nos. 2,913,327, 2,983,747, 3,133,947,3,175,897 and 3,185,720 for example. However, the use of thesethiocarbamates as reactive intermediates to form other compounds thathave pesticidal activity is unexpected.

In order to illustrate the merits of the present invention, thefollowing examples are provided:

EXAMPLE I A mixture was formed which contained 12.2 g. (0.06 mole) ofm-chloroperoxybenzoic acid in 200 cc. of chloroform. This solution wasthen cooled in an ice bath to 3C. Then, 9.5 g. (0.05 mole) of S-ethyldipropylthiocarbamate was rapidly added and the temperature rose rapidlyto 35C. and then decreased. The flask containing the reaction mixturewas placed under refrigeration for about an hour wherein white solidcrystals were observed. The solution was kept under refrigeration for 24hours and then was filtered while in the cold condition. It was thenwashed with chloroform and then was dried. The combined filtrate waswashed with 3 portions of cc. of 5% sodium carbonate solution, 1 portionof 100 cc. of water, dried over magnesium sulfate and concentrated on arotary evaporator under water pump vacuum, to yield 10.1 g. of product,n 1.4834.

EXAMPLE 2 E i i c,n,, can-LL- N A solution was formed containing 17.2 g.of mchloroperoxybenzoic acid in 200 cc. of methylene chloride.Thereafter, 10.9 g. (0.05 mole) of S-ethyl diisobutylthiocarbamate wasadded rapidly when the temperature of the solution was 18C. The solutionrose rapidly to a temperature of 30C., wherein the reaction mass wasplaced in an ice bath to reduce the temperature. After a period of 3hours the cold mixture was filtered and the cake was washed with 2portions of 25 cc. of methylene chloride. The combined filtrate waswashed with 4 portions of 100 cc. of 5% solution of sodium carbonate,then 2 portions of 100 cc. of water, dried over magnesium sulfate andconcentrated in a rotary evaporator under water pump vacuum to yield11.0 g. of product, m, 1.4718.

EXAMPLE 3 A solution was formed in a reaction vessel which contained22.3 g. (0.11 mole) of m-chloroperoxybenzoic acid in 300 cc. ofmethylene chloride. Then, 10.8 g. (0.05 mole) of S-ethylcyclohexylethylthiocarbamate was added rapidly when the temperature was35C. The temperature rose to 41C., wherein the temperature began todecrease and additional heat was applied to maintain the temperature of41C. The cold mixture was filtered and the cake was washed with 2portions of 25 cc. of methylene chloride. The combined filtrate waswashed with four portions of 100 cc. of 5% sodium carbonate solution andthen two portions of 100 cc. of water, dried over magnesium sulfate andconcentrated in a rotary evaporator, first under water pump vacuum andfinally under high vacuum to produce 11.9 g. of product, n 1.4911.

EXAMPLE 4 E .c n c u -s- -N A solution was formed containing 11.2 g.(0.055 mole) of m-chloroperoxybenzoic acid in 200 cc. of methylenechloride. Then, 10.8 g. (0.05 mole of S- ethylcyclohexylethylthiocarbamate was added rapidly when the temperature wasat 15.5C. The temperature was allowed to rise to l4.5C. and maintainedfor 2 hours. Thereafter, the temperature was allowed to reach 19.5C. Themixture was filtered and the cake was washed with 2 portions of 25 cc.methylene chloride and dried in the oven. The combined filtrate waswashed with 4 portions of 100 cc. of solution of so dium carbonate and 2portions of 100 cc. of water, dried over magnesium sulfate andconcentrated in a rotary evaporator, first under water pump vacuum andfinally under high vacuum to yield 10.4 g. of product. my 1.5120.

A solution was formed containing 10.7 g. of mchloroperoxybenzoic acid in200 cc. of methylene chloride. The solution was then placed in a dry icebath to maintain a temperature of-l 6C. Thereafter, 9.4 g. (0.05 mole)of S-ethyl allylpropylthiocarbamate was added rapidly and thetemperature rose to l4.5C. The reaction was allowed to carry out for 2hours. During the reaction the temperature was allowed to go to 155C.and thereafter was taken back down to 1C. The mixture was filtered andthe cake was washed with 2 portions of 25 cc. methylene chloride. Thecombined filtrate was washed with 4 portions of 100 cc. of 5% solutionof sodium carbonate and 2 portions of 100 cc. of water, dried overmagnesium sulfate and concentrated in a rotary evaporator, first underwater pump vacuum and finally under high vacuum to yield 9.0 g. ofproduct, n l.50l5.

EXAMPLE 6 O O CH CH=CH C H,,--SCN cH.. cH=cH A solution was formedcontaining 10.7 g. (0.525

mole) of m-chloroperoxybenzoic acid in 200 cc. of methylene chloride ina reaction vessel. The solution was cooled to -10... cl, wherein 9.3 g.(0.05 mole) of S-ethyl diallylthiocarbamate was added rapidly. Then,

'the solution rose to 15C. The reaction was allowed to be carried outfor 1.5 hours. At the end of this time the reaction was allowed to reach185C. The cold mixture was filtered and the cake washed with 2 portionsof 25 cc. of methylene chloride. The combined filtrate was washed with 4portions of cc. of 5% so dium carbonate solution and 2 portions of 100cc. of water, dried over magnesium sulfate and concentrated in a rotaryevaporator to yield 8.8 g. of product, n 1.5144.

chloroperoxybenzoic acid dissolved therein. This solution was cooled tol5C., wherein 8.6 g. (0.05 mole) of S-ethylmethy1-a-methylpropargylthiocarbamate was added rapidly. At the end of 2hours the reaction was removed from the ice bath and allowed to reach21.5C., wherein the reaction was worked up in a similar manner as setforth in the previous example to yield 6.9g. of product, n 1.5147.

Y EXAMPLE 8 O (I) C H A solution was formed containing 200 cc. ofmethylene chloride and 1 1.6 g. of S-3-chloropropyldiethylthiocarbamatedissolved therein. This solution was cooled to -17C. in a dry ice bath,wherein 10.0 g. of mchloroperoxybenzoic acid was added rapidly. After 2hours the reaction was removed from the dry ice bath and allowed toreach C. wherein the reaction was worked-up in a similar manner as setforth in the previous example to yield 11.1 g. of product, n 1.5107.

Other compounds were prepared in an analogous manner starting with theappropriate starting materials as outlined above. The following is atable of compounds representative of those embodied by the presentinvention. Compound numbers have been assigned to them and are used foridentification throughout the balance of the specification.

HERBlClDAL SCREENING TESTS 6 As previously mentioned, the novelcompounds herein described are phytotoxic compounds which are useful andvaluable in controlling various plant species. Compounds of thisinvention are tested as herbicides in the following manner.

Pre-emergence Herbicide Screening Test Using an analytical balance, 20mg. of the compound to be tested is weighed out on a piece of glassineweighing paper. The paper and compound are placed in a 30 ml. wide-mouthbottle and 3 ml. of acetone containing 0 1% Tween 20 is added todissolve the compound. If. the

lb./sq. inch. The rate of application is 8 lb./acre and the spray volumeis 143 gaL/acre.

On the day preceding treatment, the styrofoam flat which is 7 incheslong, 5 inches wide and 2.75 inches deep is filled to a depth of 2inches with loamy sand soil. Seeds of seven different weed species areplanted in individual rows using one species per row across the width ofthe flat. The seeds are covered with soil so that they are planted at adepth of 0.5 inch. The seeds used are hairy crabgrass (Digitariasanguinalis), yellow foxtail (Setaria glauca), watergrass (Echinochloacrusgalli), red oat (Avena sativa), redroot pigweed (Amaranthusretroflexus), Indian mustard (Brassica juncea) and curly dock (Rumexcrispus). Ample seeds are planted to give about 20 to 50 seedlings perrow after emergence depending on the size of the plants.

After treatment, the flats are placed in the greenhouse at a temperatureof 70 to 85F. and watered by sprinkling. Two weeks after treatment, thedegree of injury or control is determined by comparison with untreatedcheck plants of the same age. The injury rating from 0 to 100% isrecorded for each species as per cent control with 0% representing noinjury and 100% representing complete kill.

Post-emergence Herbicide Screening Test Seeds of six plant species,including hairy crabgrass, watergrass, red oat, mustard, curly dock andPinto bean (Phaseolus vulgaris) are planted in the Styrofoam flats asdescribed above for pre-emergence screening. The flats are placed in thegreenhouse at 70-85F. and watered daily with a sprinkler. About to 14days after planting when the primary leaves of the bean plants arealmost fully expanded and the first trifoliate leaves are just startingto form, the plants are sprayed. The spray is prepared by weighing outmg. of the test compound, dissolving it in 5 ml. of acetone containing1% Tween 20 and then adding 5 ml. of water. The solution is sprayed onthe foliage using a No. 152 DeVilbiss atomizer at an air pressure of 5lb./sq. inch. The spray concentration is 0.2% and the rate is 8lb./acre. The spray volume is 476 gal./acre.

Injury ratings are recorded 14 days after treatment. The rating systemis the same as described above for the pre-emergence test.

The results of these tests are shown in Table 11.

TABLE II HERBICIDAL ACTIVITY SCREENING RESULTS TABLE lI-ContinuedHERBlClDAL ACTlVlTY SCREENING RESULTS Compound Per Cent Control* at 8lb./A

Number Pre-emergence Post-emergence 2l 81 57 22 84 23 87 70 24 92 47 2599 28 26 97 64 27 91 74 28 60 52 29 58 60 30 47 53 31 46 0 34 91 83 3596 76 36 82 37 94 74 38 98 84 39 99 73 40 93 78 4l 99 71 42 79 43 64 2744 99 66 45 97 78 46 91 67 47 71 25 49 63 6l 5O 81 65 51 82 68 52 73 6353 63 20 55 95 77 2 56 3 l9 6 l3 7 O l0 3 32 0 10 33 0 10 48 0 15 54 018 Average for seven plant species in the pre-emergence test and for sixplant species in the post-emergence test.

The compounds of the present invention can be used in any convenientform. Thus, the compounds can be made into emulsifiable liquids,emulsifiable concentrates, liquid, wettable powder, powders, granular orany other convenient form, and applied to the soil to control theundesired vegetation.

The terms lower alkyl, alkenyl and alkynyl are meant to include thosecompounds having straight or branced chain configurations having fromone to six carbon atoms, inclusive.

What is claimed is:

1. A process for manufacturing a pesticidal compound corresponding tothe following formula:

wherein n is l or 2; R is selected from the group consisting of loweralkyl, lower haloalkyl, lower alkoxyalkenyl and lower alkenyl; R and Rcan be the same or different and are selected from the group consistingof lower alkyl, cyclohexyl, lower alkylcyclohexyl, lower alkenyl andlower alkynyl; comprising the steps of:

a. combining an oxidizing agent selected from peracetic acid andm-chloroperoxybenzoic acid and a thiocarbamate compound in a solventsystem; said thiocarbamate having the following formula:

60C.; R c. said oxidizing agent being present in an amount of |l atleast one stoichiometric equivalent and not more than two stoichiometricequivalents.

R2 2. The process as set forth in claim 1 wherein said oxidizing agentis m-chloroperoxybenzoic acid.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO.3,896,169 DATED July 22, 1975 INVENTOR(S) Harry Tilles and John E.Casida It is certified that error appears in the above-identified patentand that said Letters Patent are hereby corrected as shown below:

ASSIGNEE: STAUFFER CHEMICAL COMPANY, New York, N. Y.

Signed and Scaled this First Day of February 1977 [SEAL] A ttesr:

RUTH C. MASON Arresting Officer C. MARSHALL DANN Commissioner oflalemsand Trademarks

1. A PROCESS FOR MANUFACTURING A PESTICIDAL COMPOUND CORRESPONDING TOTHE FOLLOWING FORMULA:
 2. The process as set forth in claim 1 whereinsaid oxidizing agent is m-chloroperoxybenzoic acid.